The present invention relates generally to disk drives for storing data. More specifically, the present invention relates to a fluid deflector that reduces air turbulence near a transducer assembly, reduces track misregistration and inhibits damage to data on a storage disk of the disk drive.
Disk drives are widely used in computers and data processing systems for storing information in digital form. These disk drives commonly use one or more rotating storage disks to store data. Each storage disk typically includes a data storage surface on each side of the storage disk. These storage surfaces are divided into a plurality of narrow, annular regions of different radii, commonly referred to as xe2x80x9ctracksxe2x80x9d. Typically, a positioner is used to move an E-block and a transducer assembly having a data transducer over each data storage surface of each storage disk. The data transducer transfers information to and from the storage disk when positioned over the appropriate track of the storage surface.
The need for increased storage capacity and compact construction of the disk drive has led to the use of storage disks having increased track density or decreased track pitch, i.e., more tracks per inch. As the tracks per inch increase, the ability to maintain the data transducer over a target track becomes more difficult. More specifically, as track density increases, it is necessary to reduce the positioning error of the data transducer proportionally. With these systems, the accurate and stable positioning of the data transducer is critical to the accurate transfer and/or retrieval of information from the storage disk.
Moreover, the need for decreasing data transfer times has led to ever-increasing rotation speeds of the storage disks. However, as the storage disks rotate, air or other fluids in the spaces between adjacent storage disks is dragged along with the rotating disks and is accelerated outwardly toward the perimeter of the storage disks by centrifugal forces. The accelerated air is propelled from the spaces between the storage disks, resulting in low-pressure regions between adjacent storage disks. Air rushing in because of the pressure differential then fills the low-pressure regions. This repeated cycle causes chaotic and random flutter of the storage disks and turbulent air flow between the storage disks. The turbulent air flow can cause the E-block and the transducer assemblies to vibrate and become excited. The vibration makes it more difficult to position and maintain the data transducer over the target track. The turbulent air flow becomes even more significant as the storage disks rotate more rapidly and are positioned increasingly closer together. Thus, the ability to avoid track misregistration is becoming more difficult.
Attempts to reduce track misregistration caused by air turbulence include positioning an air dam or a comb at various locations in the drive housing. A typical air dam attempts to block the majority of the flow of air to the E-block and the transducer assemblies. Alternately, a comb attempts to smooth the flow of air to the E-block and the transducer assemblies. Unfortunately, existing air dams and combs can create differential pressure regions that result in increased turbulent air flow near the transducer assemblies and the E-block.
Another problem for disk drives is that data recorded onto the storage disks, as well as the transducer assemblies themselves, are susceptible to damage caused during startup or shutdown of the disk drive. Typically, the data transducer is secured to a slider having an air bearing surface. Once disk rotation ceases, the slider can xe2x80x9clandxe2x80x9d on the surface of the storage disk, resulting in loss of data and/or failure of the disk drive. In some disk drives, the positioner positions each slider over a landing zone on the storage disk as the disk drive powers down. This inhibits the slider from resting on an area of useful data storage during non-rotation of the storage disk.
Alternatively, other disk drives include either an OD ramp positioned near an outer diameter of the storage disk or an ID ramp positioned near an inner diameter of the storage disk. The positioner moves the transducer assemblies radially outward so that each transducer assembly slides onto the OD ramp or radially inward so that each transducer assembly slides onto the ID ramp. In either position, each slider is xe2x80x9cunloadedxe2x80x9d from the storage disk. Unfortunately, the ramps occupy valuable space in the disk drive and increase the cost of the disk drive.
In light of the above, the need exists to provide a reliable, simple, and efficient device that effectively decreases turbulent fluid flow near the transducer assemblies. Another need exists to provide a disk drive with reduced track misregistration. Still another need exists to provide a device that protects the storage disks and the transducer assemblies during shut down and startup of the disk drive. Yet another need exists to provide a disk drive that is relatively easy and cost effective to manufacture.
The present invention is directed to a disk drive that includes a transducer assembly, a rotating storage disk and a fluid deflector. The transducer assembly includes a slider. The fluid deflector includes a deflector finger that extends along the storage disk near the transducer assembly. The deflector finger redirects fluid flow away from the transducer assembly and reduces the fluid turbulence experienced by the transducer assembly. This decreases lateral vibration of the transducer assembly, inhibits excitation of the transducer assembly, and decreases the incidence and extent of track misregistration.
In one embodiment, the fluid deflector includes a first landing pad that is positioned near the storage disk. The first landing pad can be positioned near an inner diameter or an outer diameter of the storage disk. During shutdown of the disk drive, the transducer assembly is moved to engage the first landing pad to maintain the slider away from the storage disk. This reduces the likelihood of contact between the slider and the storage disk. Incorporating the landing pad into the fluid deflector saves space in the disk drive and reduces the manufacturing cost. In another embodiment, the fluid deflector can include the first landing pad positioned near the inner diameter and a second landing pad positioned near the outer diameter of the storage disk.
In still another embodiment, the deflector finger includes a side that remains substantially equidistant from the slider during movement of the slider relative to the deflector finger along the storage disk. With this design, the transducer assembly is subjected to a consistent, substantially uniform aerodynamic environment regardless of the position of the slider along the storage disk. In this embodiment, the deflector finger can be positioned in close proximity to the slider and on an upstream side of the slider. Stated another way, the deflector finger is positioned near the transducer assembly, between the transducer assembly and the flow of the fluid generated during rotation of the storage disk. In this manner, the deflector finger effectively reduces fluid turbulence and smoothes the fluid flow near the transducer assembly.
The present invention also includes a method for enhancing the reliability of a disk drive. The method includes the steps of deflecting fluid flow with a fluid deflector away from the transducer assembly.